[GMAT math practice question]
When both positive integers a and b are divided by 9, their remainders are 7. What is the reminder when a^2b is divided by 9?
A. 4
B. 3
C. 2
D. 1
E. 0
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When both positive integers a and b are divided by 9, their
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Max@Math Revolution
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The best way to approach remainder questions is to plug in a number. We shall plug in 7 for both a and b because its remainder, when divided by 9, is 7, as required by the question. Then a^2b=7^27=343, and the remainder of 343 when it is divided by 9 is 1.
Therefore, the answer is D.
Answer : D
The best way to approach remainder questions is to plug in a number. We shall plug in 7 for both a and b because its remainder, when divided by 9, is 7, as required by the question. Then a^2b=7^27=343, and the remainder of 343 when it is divided by 9 is 1.
Therefore, the answer is D.
Answer : D
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